blob: 70d91ac7275088afa2abbc12546aa890d291f082 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
|
#include <limits.h>
#include <util/singleton.H>
#include <kernel/basesegment.H>
#include <kernel/segmentmgr.H>
#include <kernel/block.H>
#include <kernel/vmmmgr.H>
BaseSegment::~BaseSegment()
{
delete iv_block;
}
void BaseSegment::init()
{
Singleton<BaseSegment>::instance()._init();
}
void BaseSegment::_init()
{
// Assign segment to segment manager.
SegmentManager::addSegment(this, SegmentManager::BASE_SEGMENT_ID);
// Create initial static 8MB block.
iv_block = new Block(0x0, 0x800000);
iv_block->setParent(this);
// Set default page permissions on block.
for (uint64_t i = 0; i < 0x800000; i += PAGESIZE)
{
// External address filled in by linker as start of kernel's
// data pages.
extern void* data_load_address;
// Don't map in the 0 (NULL) page.
if (i == 0) continue;
// Set pages in kernel text section to be read-only / executable.
if (((uint64_t)&data_load_address) > i)
{
iv_block->setPhysicalPage(i, i, VmmManager::RO_EXE_ACCESS);
}
// Set all other pages to initially be read/write. VFS will set
// permissions on pages outside kernel.
// (@TODO: Future Sprint, for now keep NORMAL_ACCESS as RWX, not RW.)
else
{
iv_block->setPhysicalPage(i, i, VmmManager::NORMAL_ACCESS);
}
}
}
bool BaseSegment::handlePageFault(task_t* i_task, uint64_t i_addr)
{
// Tail recursion to block chain.
return iv_block->handlePageFault(i_task, i_addr);
}
|